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Alzheimer's disease and Korsakoff's syndrome

Video transcript
Although everybody forgets, excessive forgetting can be a sign of a more serious problem. Dementia is the term for a decline in memory and other cognitive functions that gets to the point of interfering with daily life. Dementia results from excessive damage to brain tissue, which can be from multiple strokes or other causes. The most common form of dementia is Alzheimer's disease, or AD. Now, the exact cause of AD is still unknown, but we do know that in people with AD, their neurons die off over time. As people with AD lose their neurons and synapses, their cerebral cortex shrinks in size. The earliest symptoms of AD are memory loss, specifically the inability to encode or retrieve recent memories. Subsequent problems include difficulty with attention, planning, semantic memory, and abstract thinking. As the disease progresses, more severe language difficulties may appear, as well as greater memory loss, such as the inability to recognize close family and friends. As the disease continues to progress, people with AD may experience emotional instability and loss of control over their bodily functions. While there are many theories as to the exact cause of the disease, a definitive answer is still unknown, and the disease is terminal. We do know that people with AD experience a buildup of proteins called amyloid plaques in the brain, but how or why those plaques start to build up and exactly what role they play in the disease is still uncertain. Another neurological disorder affecting memory is Korsakoff's syndrome, which is caused by a lack of vitamin B1, or thiamine, in the brain. This disorder is strongly linked to severe malnutrition, eating disorders, or especially alcoholism, because these groups often don't ingest or are unable to process all the nutrients their bodies need, including thiamine. Thiamine is important because it's responsible for converting carbohydrates into the glucose your cells need for energy, and it's especially important for the normal functioning of your neurons. At first, a person developing Korsakoff's syndrome might have damage to certain parts of the brain, resulting in poor balance, abnormal eye movements, mild confusion, and/or memory loss. At this stage, it's actually called Wernicke's encephalopathy, which is the precursor to Korsakoff's syndrome. If Wernicke's encephalopathy is diagnosed in time, then it's possible to reverse the damage, or at least prevent more of it. If untreated, however, the disease will progress into full-blown Korsakoff's syndrome. The main symptom of Korsakoff's syndrome is severe memory loss, and this symptom is often accompanied by confabulation, which is when the patient makes up stories, sometimes to fill in the gaps in his or her memory. Unlike AD, Korsakoff's syndrome is not necessarily progressive. If diagnosed and treated, people can get better. People are often treated with thiamine injections or other medication, and they have to stay on a healthy diet and abstain from alcohol. And some people may also need to re-learn some things. The effectiveness of this treatment really depends on how early the disease is diagnosed and how well the patient follows the treatment guidelines.